System and method for distributed multi-processing security gateway

ABSTRACT

A system and method for a distributed multi-processing security gateway establishes a host side session, selects a proxy network address for a server based on network information, and using the proxy network address to establish a server side session. The proxy network address is selected such that a same processing element is assigned to process data packets from the server side session and the host side session. The network information includes a security gateway network address and a host network address. By assigning processing elements in this manner, higher capable security gateways are provided.

CROSS-REFERENCE TO RELATED APPLICATIONS

This patent application is a continuation of, and claims the prioritybenefit of, U.S. patent application Ser. No. 13/666,979 filed on Nov. 2,2012, now U.S. Pat. No. 8,595,819 issued on Nov. 26, 2013, and entitled“System and Method for Distributed Multi-Processing Security Gateway,”which in turn is a continuation of U.S. patent application Ser. No.11/501,607 filed on Aug. 8, 2006, now U.S. Pat. No. 8,332,925 issued onDec. 11, 2012, and entitled “System and Method for DistributedMulti-Processing Security Gateway.” The disclosures of all of the aboveare incorporated herein by reference in their entirety.

TECHNICAL FIELD

This invention relates generally to data networking, and morespecifically, to a system and method for a distributed multi-processingsecurity gateway.

BACKGROUND

Data network activities increases as more and more computers areconnected through data networks, and more and more applications utilizethe data networks for their functions. Therefore, it becomes moreimportant to protect the data network against security breaches.

There are currently many security gateways such as firewalls, VPNfirewalls, parental control appliances, email virus detection gateways,special gateways for phishing and spyware, intrusion detection andprevention appliances, access control gateways, identity managementgateways, and many other types of security gateways. These products aretypical implemented using a general purpose micro-processor such asIntel Pentium, an AMD processor or a SPARC processor, or an embeddedmicro-processor based on RISC architecture such as MIPS architecture,PowerPC architecture, or ARM architecture.

Micro-processor architectures are limited in their processingcapability. Typically they are capable of handling up to a gigabit persecond of bandwidth. In the past few years, data network bandwidthutilization increases at a pace faster than improvements ofmicroprocessor capabilities. Today, it is not uncommon to seemulti-gigabit per second of data network bandwidth utilization in manymedium and large secure corporate data networks. It is expected suchscenarios to become more prevailing in most data networks, includingsmall business data network, residential networks, and service providerdata networks.

The trend in the increasing usage of data networks illustrates a needfor better and higher capable security gateways, particularly in usingmultiple processing elements, each being a micro-processor or based onmicro-processing architecture, to work in tandem to protect the datanetworks.

SUMMARY

A system and method for a distributed multi-processing security gatewayestablishes a host side session, selects a proxy network address for aserver based on network information, and using the proxy network addressto establish a server side session. The proxy network address isselected such that a same processing element is assigned to process datapackets from the server side session and the host side session. Thenetwork information includes a security gateway network address and ahost network address. By assigning processing elements in this manner,higher capable security gateways are provided.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 a illustrates a secure data network.

FIG. 1 b illustrates an overview of a network address translation (NAT)process.

FIG. 1 c illustrates a NAT process for a TCP session.

FIG. 2 illustrates a distributed multi-processing security gateway.

FIG. 3 illustrates a dispatching process.

FIG. 4 illustrates a proxy network address selection process.

DETAILED DESCRIPTION

FIG. 1 a illustrates a secure data network. Security gateway 170protects a secure data network 199.

In one embodiment, secure data network 199 is a residential datanetwork. In one embodiment, secure data network 199 is a corporatenetwork. In one embodiment, secure data network 199 is a regionalcorporate network. In one embodiment, secure data network 199 is aservice provider network.

In one embodiment, security gateway 170 is a residential broadbandgateway. In one embodiment, security gateway 170 is a corporatefirewall. In one embodiment, security gateway 170 is a regional officefirewall or a department firewall. In one embodiment, security gateway170 is a corporate virtual private network (VPN) firewall. In oneembodiment, security gateway 170 is an Internet gateway of a serviceprovider network.

When host 130 inside secure data network 199 accesses a server 110outside secure data network 199, host 130 establishes a session withserver 110 through security gateway 170. Data packets exchanged withinthe session, between host 130 and server 110, pass through securitygateway 170. Security gateway 170 applies a plurality of securitypolicies during processing of the data packets within the session.Examples of security policies include network address protection,content filtering, virus detection and infestation prevention, spywareor phishing blocking, network intrusion or denial of service prevention,data traffic monitoring, or data traffic interception.

FIG. 1 b illustrates an overview of a network address translation (NAT)process.

In one embodiment, a security policy is to protect network address ofhost 130. Host 130 uses a host network address 183 in a session 160between host 130 and server 110. In one embodiment, the host networkaddress 183 includes an IP address of host 130. In another embodiment,the host network address 183 includes a session port address of host130.

Security gateway 170 protects host 130 by not revealing the host networkaddress 183. When host 130 sends a session request for session 160 tosecurity gateway 170, the session request includes host network address183.

Security gateway 170 establishes host side session 169 with host 130.Host 130 uses host network address 183 in session 169.

Security gateway 170 selects a proxy network address 187. Securitygateway 170 uses proxy network address 187 to establish server sidesession 165 with server 110.

Server side session 165 is the session between security gateway 170 andserver 110. Host side session 169 is the session between securitygateway 170 and host 130. Session 160 includes server side session 165and host side session 169.

Security gateway 170 performs network address translation (NAT) processon session 160. Security gateway 170 performs network addresstranslation process on data packets received on server side session 165by substituting proxy network address 187 with host network address 183.Security gateway 170 transmits the translated data packets onto hostside session 169. Similarly, security gateway 170 performs networkaddress translation process on data packets received on host sidesession 169 by substituting host network address 183 with proxy networkaddress 187. Security gateway 170 transmits the translated data packetsonto server side session 165.

In one embodiment, session 160 is a transmission control protocol (TCP)session. In one embodiment, session 160 is a user datagram protocol(UDP) session. In one embodiment, session 160 is an internet controlmessaging protocol (ICMP) session. In one embodiment, session 160 isbased on a transport session protocol on top of IP protocol. In oneembodiment, session 160 is based on an application session protocol ontop of IP protocol.

FIG. 1 c illustrates a NAT process for a TCP session.

Host 130 sends a session request 192 for establishing a session 160 withserver 110. Session 160 is a TCP session. Session request 192 includeshost network address 183 and server network address 184. Securitygateway 170 receives session request 192. Security gateway 170 extractshost network address 183 from session request 192. Security gateway 170determines a proxy network address 187. In one embodiment, host networkaddress 183 includes a host's IP address, and security gateway 170determines a proxy IP address to substitute host's IP address. In oneembodiment, host network address 183 includes a host's TCP port number,and security gateway 170 determines a proxy TCP port number tosubstitute host's TCP port number. Security gateway 170 extracts servernetwork address 184 from session request 192. Security gateway 170establishes a server side session 165 with server 110 based on servernetwork address 184 and proxy network address 187. Server side session165 is a TCP session.

Security gateway 170 also establishes a host side session 169 with host130 by responding to session request 192.

After establishing server side session 165 and host side session 169,security gateway 170 processes data packets from server side session 165and host side session 169.

In one embodiment, security gateway 170 receives a data packet 185 fromserver side session 165. Data packet 185 includes server network address184 and proxy network address 187. Security gateway 170 extracts servernetwork address 184 and proxy network address 187. Security gateway 170determines host side session 169 based on the extracted networkaddresses. Security gateway 170 further determines host network address183 from host side session 169. Security gateway 170 modifies datapacket 185 by first substituting proxy network address 187 with hostnetwork address 183. Security gateway 170 modifies other parts of datapacket 185, such as TCP checksum, IP header checksum. In one embodiment,security gateway 170 modifies payload of data packet 185 by substitutingany usage of proxy network address 187 with host network address 183.

After security gateway 170 completes modifying data packet 185, securitygateway 170 transmits the modified data packet 185 onto host sidesession 169.

In a similar fashion, security gateway 170 receives a data packet 188from host side session 169. Data packet 188 includes server networkaddress 184 and host network address 183. Security gateway 170 extractsserver network address 184 and host network address 183. Securitygateway 170 determines server side session 165 based on the extractednetwork addresses. Security gateway 170 further determines proxy networkaddress 187 from server side session 165. Security gateway 170 modifiesdata packet 188 by first substituting host network address 183 withproxy network address 187. Security gateway 170 modifies other parts ofdata packet 188, such as TCP checksum, IP header checksum. In oneembodiment, security gateway 170 modifies payload of data packet 188 bysubstituting any usage of host network address 183 with proxy networkaddress 187.

After security gateway 170 completes modifying data packet 188, securitygateway 170 transmits the modified data packet 188 onto server sidesession 165.

FIG. 2 illustrates a distributed multi-processing security gateway.

In one embodiment, security gateway 270 is a distributedmulti-processing system. Security gateway 270 includes a plurality ofprocessing elements. A processing element 272 includes a memory module.The memory module stores host network addresses, proxy network addressesand other information for processing element 272 to apply securitypolicies as described in FIG. 1. Processing element 272 has a processingelement identity 273.

Security gateway 270 includes a dispatcher 275. Dispatcher 275 receivesa data packet and determines a processing element to process the datapacket. Dispatcher 275 typically calculates a processing elementidentity based on the data packet. Based on the calculated processingelement identity, security gateway 270 assigns the data packet to theidentified processing element for processing.

In one embodiment, dispatcher 275 receives a data packet 288 from hostside session 269 and calculates a first processing element identitybased on the host network address and server network address in datapacket 288. In another embodiment dispatcher 275 receives a data packet285 from server side session 265 and calculates a second processingelement identity based on the proxy network address and server networkaddress in data packet 285.

Security gateway 270 includes a network address selector 277. Networkaddress selector 277 selects a proxy network address based on networkinformation. The network information includes a host network addressobtained in a session request for session 260 and a security gatewaynetwork address. Other types of network information may also be used.The proxy network address is used to establish server side session 265.The proxy network address is selected such that the first processingelement identity and the second processing element identity calculatedby dispatcher 275 are the same. In other words, a same processingelement is assigned to process data packet 285 from server side session265 and data packet 288 from host side session 269.

FIG. 3 illustrates a dispatching process.

Dispatcher 375 calculates a processing element identity based on twonetwork addresses obtained from a data packet 385 of session 360.Session 360 includes host side session 369 and server side session 365.The two network addresses of host side session 369 are server networkaddress and host network address. The two network addresses of serverside session 365 are proxy network address and server network address.Dispatcher 375 calculates to the same processing element identity forhost side session 369 and server side session 365.

In one embodiment, dispatcher 375 calculates based on a hashingfunction.

In one embodiment, dispatcher 375 computes a sum by adding the twonetwork addresses. In one example, dispatcher 375 computes a sum byperforming a binary operation, such as an exclusive or (XOR) binaryoperation, or an and (AND) binary operation, onto the two networkaddresses in binary number representation. In one example, dispatcher375 computes a sum by first extracting portions of the two networkaddresses, such as the first 4 bits of a network address, and applies anoperation such as a binary operation to the extracted portions. In oneexample, dispatcher 375 computes a sum by first multiplying the twonetwork addresses by a number, and by applying an operation such asaddition to the multiple.

In one embodiment, dispatcher 375 computes a processing element identityby processing on the sum. In one embodiment, there are 4 processingelements in security gateway 370. In one example, dispatcher 375extracts the first two bits of the sum, and interprets the extracted twobits as a numeric number between 0 and 3. In one example, dispatcher 375extracts the first and last bit of the sum, and interprets the extractedtwo bits as a numeric number between 0 and 3. In one example, dispatcher375 divides the sum by 4 and determines the remainder of the division.The remainder is a number between 0 and 3.

In one embodiment, security gateway 370 includes 8 processing elements.Dispatcher 375 extracts 3 bits of the sum and interprets the extractedthree bits as a numeric number between 0 and 7. In one example,dispatcher 375 divides the sum by 8 and determines the remainder of thedivision. The remainder is a number between 0 and 7.

In one embodiment, a network address includes an IP address and asession port address. Dispatcher 375 computes a sum of the IP addressesand the session port addresses of the two network addresses.

Though the teaching is based on the above description of hashingfunctions, it should be obvious to the skilled in the art to implement adifferent hashing function for dispatcher 375.

FIG. 4 illustrates a proxy network address selection process.

Network address selector 477 selects a proxy network address 487 for ahost network address 483. In one embodiment, host network address 483includes a host IP address 484 and a host session port address 485;proxy network address 487 includes a proxy IP address 488 and a proxysession port address 489. Proxy network address 487 is selected suchthat dispatcher 475 calculates to the same processing element identityon host side session 469 and server side session 465. Session 460includes server side session 465 and host side session 469.

In one embodiment, the selection process is based on the dispatchingprocess, illustrated in FIG. 3. In one example, dispatcher 475 uses themethod of computing the sum of two IP addresses, and two session portaddresses, and then divides the sum by 4. In one embodiment, networkaddress selector 477 first selects proxy IP address 488. Network addressselector 477 then selects proxy session port address 489 such that whenusing the method on server network address 490 and host network address483 dispatcher 475 calculates the same processing element identity aswhen using the method on server network address 490 and proxy networkaddress 487.

In one example, dispatcher 475 computes a sum from a binary operator XORof the two network addresses, and extracts the last 3 digits of the sum.Network address selector 477 selects a proxy session port address 489that has the same last 3 digits of the host session port address 485.

In one embodiment, security gateway 470 performs network addresstranslation process for a plurality of existing sessions. Networkaddress selector 477 checks if the selected proxy network address 487 isnot used in the plurality of existing sessions. In one embodiment,security gateway 470 includes a datastore 479. Datastore 479 stores aplurality of proxy network addresses used in a plurality of existingsessions. Network address selector 477 determines the selected proxynetwork address 487 is not used by comparing the selected proxy networkaddress 487 against the stored plurality of proxy network addresses andnot finding a match.

In one embodiment, a processing element includes network addressselector. A processing element receives a data packet assigned bysecurity gateway based on a processing element identity calculated bydispatcher. In one embodiment, the processing element determines thatthe data packet includes a session request. The network address selectorin the processing element selects a proxy network address based on thehost network address in the session request as illustrated in FIG. 4.

In one embodiment, a particular first processing element includesnetwork address selector. A second processing element without networkaddress selector receives a data packet and determines that the datapacket includes a session request. The second processing element sendsthe data packet to the first processing element using, for example, aremote function call. The first processing element receives the datapacket. The network address selector selects a proxy network addressbased on the host network address in the session request.

In one embodiment, datastore is implemented in the memory module of aprocessing element. In one embodiment, the plurality of proxy networkaddresses in datastore are stored in each of the memory modules of eachof the processing elements. In one embodiment, the plurality of proxynetwork addresses in datastore are stored in the memory modules in adistributive manner, with the proxy network addresses used in thesessions processed by a processing element stored in the memory moduleof the processing element.

In one embodiment, security gateway includes a memory shared by theplurality of process elements. Security gateway partitions the sharedmemory into memory regions. A process element has access to a dedicatedmemory region, and does not have access to other memory regions.

In one embodiment, security gateway includes a central processing unit.In one embodiment, the central process unit includes a plurality ofprocessing threads such as hyper-thread, micro-engine or otherprocessing threads implemented in circuitry such as application specificintegrated circuit (ASIC) or field programmable gate array (FPGA). Aprocessing element is a processing thread.

In one embodiment, a central processing unit includes a plurality ofmicro-processor cores. A processing thread is a micro-processor core.

In one embodiment, a security policy is for virus detection or blocking.In one embodiment, a security policy is for phishing detection orblocking. In one embodiment, a security policy is for traffic quotaenforcement. In one embodiment, a security policy is for lawful datainterception.

In one embodiment, the NAT process is for a UDP session. In oneembodiment, security gateway receives a UDP packet. In one embodiment,security gateway determines that the UDP packet is not from an existingsession. Security gateway processes the UDP packet as a session request.

In one embodiment, the NAT process is for an ICMP session. In a similarfashion, security gateway processes an ICMP packet from a non-existingsession as a session request.

What is claimed is:
 1. A method for providing a network gateway,comprising: receiving by the network gateway a session request for asession between a host and a server, the session request comprising ahost network address and a server network address; establishing by thenetwork gateway a host side session between the network gateway and thehost, the network gateway comprising a plurality of processors;selecting by the network gateway a proxy network address for the hostbased on network information, the network information comprising thehost network address and a network gateway network address, wherein theproxy network address is selected such that a calculated first processoridentity by the network gateway is the same as a calculated secondprocessor identity by the network gateway; establishing by the networkgateway a server side session between the network gateway and the serverusing the selected proxy network address; in response to receiving afirst data packet from the host side session, calculating by the networkgateway the first processor identity, comprising: assigning a firstprocessor with the first processor identity to process the first datapacket, modifying the first data packet by substituting the host networkaddress in the first data packet with the selected proxy networkaddress, and sending the modified first data packet to the server sidesession; and in response to receiving a second data packet from theserver side session, calculating by the network gateway the secondprocessor identity, comprising: assigning a second processor with thesecond processor identity to process the second data packet.
 2. Themethod of claim 1, wherein the calculated first processor identity bythe network gateway is based at least in part on the server networkaddress and the host network address.
 3. The method of claim 1, whereinthe calculated second processor identity by the network gateway is basedat least in part on the proxy network address and the server networkaddress.
 4. The method of claim 1, wherein the assigning the firstprocessor with the first processor identity to process the first datapacket comprises: processing the first data packet according to asecurity policy by the first processor.
 5. The method of claim 4,wherein the security policy comprises one or more of the following:intrusion detection; virus detection; traffic quota violation; andlawful data interception.
 6. The method of claim 1, wherein theassigning the second processor with the second processor identity toprocess the second data packet comprises: processing the second datapacket according to a security policy by the second processor.
 7. Themethod of claim 6, wherein the security policy comprises one or more ofthe following: virus detection; traffic quota violation; lawful datainterception; and phishing.
 8. The method of claim 1, wherein theselected proxy network address comprises an IP address.
 9. The method ofclaim 8, wherein the selected proxy network address further comprises aTCP or UDP port.
 10. The method of claim 1, wherein the calculated firstprocessor identity by the network gateway is based at least in part on acomputed sum of an IP address for the server network address and an IPaddress for the host network address.
 11. The method of claim 1, whereinthe calculated second processor identity by the network gateway is basedat least in part on a computed sum of an IP address for the proxynetwork address and an IP address for the server network address.
 12. Acomputer program product comprising a non-transitory computer readablemedium having a computer readable program, wherein the computer readableprogram when executed on a computer causes the computer to: receive asession request for a session between a host and a server, the sessionrequest comprising a host network address and a server network address;establish a host side session between a network gateway and the host,the network gateway comprising a plurality of processors; select a proxynetwork address for the host based on network information, the networkinformation comprising the host network address and a network gatewaynetwork address, wherein the proxy network address is selected such thata calculated first processor identity by the network gateway is the sameas a calculated second processor identity by the network gateway;establish a server side session between the network gateway and theserver using the selected proxy network address; in response toreceiving a first data packet from the host side session, calculate thefirst processor identity, comprising: assign a first processor with thefirst processor identity to process the first data packet, modify thefirst data packet by substituting the host network address in the firstdata packet with the selected network address, and send the modifiedfirst data packet to the server side session; and in response toreceiving a second data packet from the server side session, calculatethe second processor identity, comprising: assign a second processorwith the second processor identity to process the second data packet.13. The computer program product of claim 12, wherein the calculate thefirst processor identity is based at least in part on the server networkaddress and the host network address.
 14. The computer program productof claim 12, where in the calculate the second processor identity isbased at least in part on the proxy network address and the servernetwork address.
 15. The computer program product of claim 12, whereinthe assign the first processor with the first processor identity toprocess the first data packet comprises: process the first data packetaccording to a security policy by the first processor.
 16. The computerprogram product of claim 15, wherein the security policy comprises oneor more of the following: intrusion detection; virus detection; trafficquota violation; and lawful data interception.
 17. The computer programproduct of claim 12, wherein the assign the second processor with thesecond processor identity to process the second data packet comprises:process the second data packet according to a security policy by thesecond processor.
 18. The computer program product of claim 17, whereinthe security policy comprises one or more of the following: virusdetection; traffic quota violation; lawful data interception; andphishing.
 19. The computer program product of claim 12, wherein theselected proxy network address comprises an IP address.
 20. The computerprogram product of claim 19, wherein the selected proxy network addressfurther comprises a TCP or UDP port.
 21. The computer program product ofclaim 12, wherein the calculated first processor identity is based atleast in part on a computed sum of an IP address for the server networkaddress and an IP address for the host network address.
 22. The computerprogram product of claim 12, wherein the calculated second processoridentity is based at least in part on a computed sum of an IP addressfor the proxy network address and an IP address for the server networkaddress.